JOURNAL OF NANOSTRUCTURES
Year:2015 | Volume:5 | Issue:4|Papers Count:16

A new type of cation-exchange nanocomposite membranes was prepared by in-situ formation of ZnO nanoparticles in a blend containing sulfonated poly (2, 6-dimethyl-1, 4-phenylene oxide) and sulfonated polyvinylchloride via a simple one-step chemical method. As-synthesized nanocomposite membranes were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. The SEM images showed that ZnO nanoparticles were uniformly dispersed throughout the polymeric matrices. The effect of addtiive loading on physicochemical and electrochemical properties of prepared cationexchange nanocomposite membranes was studied. Various characterizations revealed that the incorporation of different amounts of ZnO nanoparticles into the basic membrane structure had a significant influence on the membrane performance and could improve the electrochemical properties.

Sulfated titania nanoparticles (SO4 2-/TiO2 NPs) were synthesized using titanium tetraisopropoxide (TTIP) by the sol-gel method.The structure and morphology of the prepared nanocatalyst was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) methods as well as Fourier transform infrared (FT-IR) and energy dispersive X-ray (EDX) spectroscopy. The obtained nanoparticles were used as an efficient, reusable and environmentally friendly catalyst for the synthesis of polyhydroquinoline (PHQ) derivativesvia a one-pot multicomponent reaction of various aldehydes, ammonium acetate and 1, 3-dicarbonyl compounds under reflux conditions.The desired Hantzsch esters were obtained in good to excellent yields and short reaction times. The SO42-/TiO2 NPs could be recycled at least three times without significant loss of their catalytic activity.

In this work, a new hybrid organometallic-inorganic hybrid nanomaterial was prepared by immobilization of acetyl ferrocene on the surface of magnetite nanoparticles. Covalent grafting of silica coated magnetite nanoparticles (SCMNPs) with 3-aminopropyl triethoxysilane gave aminopropyl-modified magnetite nanoparticles (AmpSCMNPs). Then, Schiff base condensation of AmpSCMNPs with acetyl ferrocene resulted in the preparation of acferro-SCMNPs hybrid nanomaterial. Characterization of the prepared nanomaterial was performed with different physicochemical methods such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). VSM analysis showed superparamagnetic properties of the prepared nanomaterial and TEM and SEM analyses indicated the relatively spherical nanoparticles with 15 nm average size.

Graphene nanostructures were synthesized by Hummer method.1, 3, 5 and 7 wt% of graphene nanostructures were suspended in certain amount of acetone on a mechanical stirrer and stirred then added to epoxy resin. After 4 hours, solution and Graphene platelets (GPs) were prepared. Nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy. The electromagnetic interference shielding was studied by reflection loss (RL). According to the results, the multilayered graphene 3% wt of has a completely smooth surface and its absorption average and maximum are reported as -13.5 dB and -30.3 dB.

Nanostructured RuO2 powders were synthesized via a hydrothermal method at 180 °C for 12 h using 1 and 2 M NaOH aqueous solutions. The structure of the obtained nanomaterials was investigated by powder X-ray diffraction (PXRD) technique. The morphology the obtained materials were studied by field emission scanning electron microscope (FESEM). The technique showed that with changing the reaction rout, the homogeneity of the size and morphology of the synthesized nanomaterials were changed. It was found that the morphology of the obtained materials were spherical particles using 2 M NaOH aqueous solution. Catalytic performance of the synthesized nanomaterials was investigated in Biginelli reactions for the one-pot synthesis of 3, 4-dihydropyrimidin-2 (1H) -ones (DHPMs) using Benzaldehyde derivatives, urea and ethylacetoacetate as raw materials. Experimental design method was used to obtain optimized reaction conditions. It was found that the optimized conditions were 0.028 g of catalyst, 110oC reaction temperature and 66 min reaction time.

In this work we synthesized Nano hydroxyapatite (HAp) by Solgel method, Then we functionalized hydroxyapatite nanoparticle by use of 3-Aminopropyl trimethoxysilane (APTMS), to improve the loading and control release of sulfasalazine drug bonded to APTMS. The drug release patterns from Sulfasalazine loaded HAp nanoparticles at pH value 8 For 6h, Sulfasalazine loaded functionalized HAp nanoparticles (Sulfasalazine loaded HAp-APTMS) at pH value 8 as in the intestine for 48h. Moreover, the functionalized HAp showed relatively slower release rate of sulfasalazine compare with non functionalized HAp. because the strong ionic interaction between NH2 group in sulfasalazine in HAp-APTMS. On other side, the functionalized HAp loaded more drug than pure HAp. The synthesized nanoparticles and functionalized HAp characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier transform infrared (FT-IR) and UV/Vis analysis techniques. Then the obtained material was studied in the simulated body fluid (SBF) to this investigated storage and release properties.

The Knoevenagel condensation of aromatic aldehydes with barbituric acid, dimedone and malononitrile occurred in the presence of BF3/nano-g-Al2O3 at room temperature in ethanol. This catalyst is characterized by powder X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and energydispersive X-ray spectroscopy (EDS).

Cd1-xMnxS (x=0, 0.1, 0.2) nanoparticles, prepared by coprecipitation method under ultrasonic irradiation, were studied by means of X-ray diffraction, scanning electron microscopy, FTIR and UV-Vis spectroscopy measurements. The average particle size of nanoparticles from the scanning electron microscopy image is about 20-30 nm. Results show that partial substitution of Cd by Mn leads to a reduction in lattice parameters and enhancement of band gap energy. This is attributed to the nanometric grain size and quantum confinement effects. The particle size is calculated to be around 2 nm that is almost in agreement with the crystallite size estimated from the XRD result.

In this work firstly Fe2O3 nanoparticles were synthesized via a simple chemical method. Properties of the product were examined by X-ray diffraction pattern (XRD), Scanning electron microscope (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Vibrating sample magnetometer (VSM) shows nanoparticles exhibit ferromagnetic behavior. To continue some of the 2-naphthol condensed 1, 3-oxazinone derivatives employing one-pot condensation reaction in the presence of Fe2O3 nanoparticles as an acid catalyst were described. The present methodology offers several advantages, viz. high yields, clean reaction, short reaction times, recyclability of the catalyst and simple workup procedure.

In this research zinc oxide (ZnO) nano-crystalline powders were prepared by sol-gel method using zinc acetate. The ZnO nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis), Fourier transform infra-red (FT-IR) and energy dispersive X-ray (EDX) spectroscopy.The structure of nanoparticles was studied using XRD pattern. The crystallite size of ZnO nanoparticles was calculated by Debye–Scherrer formula. Morphology of nano-crystals was observed and investigated using the SEM. The grain size of zinc oxide nanoparticles were in suitable agreement with the crystalline size calculated by XRD results. The optical properties of particles were studied with UV-Vis an FTIR absorption spectrum. The Raman spectrum measurements were carried out using a micro-laser Raman spectrometer forms the ZnO nanoparticles. At the end studied the effect of calcined temperature on the photoluminescence (PL) emission of ZnO nanoparticles.

Magnetite (Fe3O4) nanoparticles have been successfully prepared by a novel one-step and surfactant-free approach utilizing ferrous ion, as a single iron source. In this manner, the reaction occurs between two aqueous solutions via the spontaneous transfer of ammonia gas from one to another in room temperature. No ferric source or oxidizing specie, oxidation controlling and capping agents are needed and the method is suited for large-scale preparation. The effects of reaction conditions on the formation of Fe3O4 were investigated using powder X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) techniques. The results have demonstrated that the pure and single phase magnetite nanoparticles were synthesized at the final pH values higher than 8. Accordingly, the formation mechanism of these nanostructures is proposed. Moreover, the vibrating sample magnetometry (VSM) measurements of the assynthesized nanoparticles show their room temperature superparamagnetic characteristic with a typical saturation magnetization of 51 emug-1.

In this paper, the effect of magnetic field on the morphology, structure and magnetic properties of electrodeposited FeCu/Cu thin films was investigated. The films were deposited on Au2PdAg/glass substrates using electrodeposition technique in potentiostatic control. The magnetic fields of 5000 and 7000 Oe were applied on deposition bath during deposition. Two series of thin films were prepared in the same deposition conditions, one in the presence and the other in absence of magnetic field and the products were compared. The results indicate that applying the magnetic field has a significant effect on the growth process, i.e. morphology, crystal structure and magnetic properties of the films. The morphology and structure of the FeCu/Cu Nano layers were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The weight percentages of the elements in the deposited multilayers were determined by energy dispersive X-ray spectroscopy (EDS). Magnetic properties of thin films were studied using the vibrating sample magnetometer (VSM).

Silver nanowires were synthesized by solvothermal method through reducing silver nitrate (AgNO3) with ethylene glycol (EG) in the presence of polyvinylpyrrolidone (PVP). In order to prevent the agglomeration of Ag+ in the initial Ag seeds formation, sodium chloride (NaCl) was added into the solution to form AgCl colloids.By dissolving AgCl in the late stages, Ag+ ions were released into the solution. So the diameters of silver nanowires could be controlled by modifying the PVP concentration. The effect of reaction time, reaction temperature, and for first time purity of EG over the shape of resulted silver nanowires were investigated. The wire, sphere and tree-like nanostructures were formed with changing these parameters. The structural and optical properties of the silver nanostructures were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and UV-visible absorption spectrophotometer. In order to synthesis silver nanowires with smaller diameters and longer lengths, the optimum molar ratio of PVP/AgNO3, reaction time, reaction temperature, and EG purity were found to be 1.5, 2.5 h, 160oC, and 99.5%, respectively.

The synthesis of polyaniline- Fe2O3 nanocomposite coating on aluminum Alloy 5052 (AA5052) surface has been investigated by using the galvanostatic method. The anticorrosion performance of polyaniline-Fe2O3 coating was investigated in 3.5% NaCl solution by the open- circuit potential (OCP), Tafel polarization technique and Electrochemical Impedance Spectroscopy (EIS). The corrosion rate of polyaniline-Fe2O3 nanocomposite coating AA5052 was found about140 times lower than bare AA5052. Corrosion potential also decreased from -0.710 V to -0.735 V versus Ag/AgCl for uncoated AA5052 and polyaniline-Fe2O3 nanocomposite coated on AA5052 electrodes, respectively. Electrochemical measurements show that polyaniline-Fe2O3 nanocomposite coated has good inhibitive properties with PE% of ~97.3% at 25 mA cm-2 current density applied on AA5052 corrosion in a chloride media. The results of this study clearly find out that the polyaniline-Fe2O3 nanocomposite has an outstanding possible to protect AA5052 against corrosion in a chloride environment.

Copper vanadate nanostructures were prepared via ex-situ precipitation approach in presence of Schiff-base ligand (N, N -׳buthylenebis (acetylacetone iminato) dianion=acacbn) as a new capping agent. The effect of different Cu sources and pH on the size, morphology and size distribution of copper vanadate nanostructures was investigated.The as-prepared products were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectrum, Electron Dispersive X-ray spectroscopy (EDX) and ultraviolet-visible (UV-Vis) spectroscopy. The optical properties of different samples were compared.

In the current study, pure TiO2 and Cr-doped TiO2 (Cr@TiO2) nanoparticles were synthesized via sol-gel method and the resulting materials were applied to prepare the porous TiO2 electrodes for dye-sensitized solar cells (DSSCs). It is hypothesized that the advantages of the doping of the metal ions into TiO2 lattice are the temporary rapping of the photogenerated electron-hole (charge carriers) by the metal dopants and the retarding charge recombination during electron migration from TiO2 to the electrode surface. Spectroscopic and microscopic findings showed that all the prepared samples consist of only anatse phase with average size of 10-15nm. In addition, relative to the bare TiO2, Cr@TiO2 absorption in visible light region was considerably improved due to the surface Plasmon phenomenon. Current-voltage (I-V) curves exhibited that the solar cells made of Cr@TiO2 nanoparticles results in higher photocurrent density than the cells made of bare TiO2. The large improvement of photovoltaic performance of the Cr-doped TiO2 cell stems from negative shift of TiO2 conduction band and retarding charge recombination. Finally, it is concluded that the proposed route in the current study is an effective way to enhance the energy conversion efficiency and overall performance of DSSC.